云南松林的林冠对土壤侵蚀的影响

研究发现滇西北高山峡谷区云南松也具有通过林冠截流减少有效雨量和降低雨滴对地表的滴溅能量，减少降雨对土壤的侵蚀程度，产生较大的直径的叶工引起的林冠滴溅效应，云南松林冠在整个雨季截留率平均达３６．２９％，使林下有效降雨仅为降雨量的６３．７１％，松林在整个雨季的林下溅蚀累积总量为４．９４ｋｇ／ｍ＾２，裸地为６．１２ｋｇ／ｍ＾２，表明松林减少１９．２８％，的溅蚀全量，但林地在雨季中后期的各阶段溅蚀全量却高

EFFECT OF YUNNAN PINE FOREST CANOPY ON SOIL EROSION

Rain is a main cause of soil erosion. Forest canopy can reduce effective rainfall, by its interception, and curtail impacting energy of raindrops to splash soil particles. On the other hand, canopy also produces large_size leave drops and causes canopy splash erosion. This study proves exist of these effects in the Yunnan pine forest. As field experiment indicated, the canopy interception of the forest averaged 36.29%, and effective rainfall under the canopy was only 63.71% of the rainfall. The total accumulated splash amount were 4.94kg/m 2 under the forest, showing a 19.28% of reduction splash detachment in the forest. The splash detachment amount over each stage of the rain season, however, were much higher under the forest than on the bare land, and the figure in the forest was 2.6 times greater than that at the later rain stage. It is suggested that, the forest is provided with effect of rainfall interception and net effect of reducing splash soil erosion, but it also affects negatively on the soil particles by causing canopy splash detachment.